cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A137635 a(n) = Sum_{k=0..n} C(2k,k)*C(2k,n-k); equals row 0 of square array A137634.

Table of values

n a(n)
0 1
1 2
2 10
3 46
4 226
5 1136
6 5810
7 30080
8 157162
9 826992
10 4376408
11 23267332
12 124179570
13 664919780
14 3570265000
15 19216805476
16 103652442922
17 560127574340
18 3031887311256
19 16435458039076
20 89213101943000
21 484839755040768
22 2637805800869740
23 14365506336197816

List of values

[1, 2, 10, 46, 226, 1136, 5810, 30080, 157162, 826992, 4376408, 23267332, 124179570, 664919780, 3570265000, 19216805476, 103652442922, 560127574340, 3031887311256, 16435458039076, 89213101943000, 484839755040768, 2637805800869740, 14365506336197816]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement.